Despite substantial improvements in the field, known optical signal couplers tend to have unacceptably high light losses, nonuniform signal distribution, or are bulky and inordinately difficult to fabricate. Many of these shortcomings such as misalignment of the fibers, result from the connectors used to join the coupler to optical fibers.
U.S. Pat. No 5,255,336 discloses an injection molded optical element, having molded optical junctions with an integrally formed input or output portion projecting outwardly from the coupler body defining an angle with a propagation axis of the element, and a continuous waveguiding profile free from lateral discontinuities. The molded coupler and housing disclosed in U.S. Pat. No. 5,255,336, are specifically designed to adapt to DNP (Dry No Polish) connectors from AMP, Inc. and thus, the molded coupler is not compatible with any other type of connector, since the ends of the fibers of the coupler are molded at a distance from one another to allow a DNP connector to be attached to each fiber without forcing the fibers from coplanarity.
The prior art process used to connect the fourteen individual fibers to the 7.times.7 type molded coupler disclosed in U.S. Pat. No. 5,255,336, is also time consuming and may result in variability in optical loss at each fiber. The fiber ends on the coupler are connected with DNP connectors which are specifically designed to connect jacketed fibers. This results in light losses since absorption of the evanescent wave energy by the black jacketing material can result in a decrease in the amount of light emerging from each fiber end.
The existing mechanism for terminating the fibers involves manually pressing the ends of each of the individual fibers onto a highly polished hot plate which produces a relative low optical loss connection. Manual termination of the fiber ends of a coupler may also result in increased excess loss and loss of uniformity. The present invention concerns improved connectors and related methods of making and using the same which improve on the shortcomings of the prior art.